NEW YORK (Reuters Health) - Nearly half of patients diagnosed with early hepatocellular carcinoma (HCC) between 1998 and 2007 did not undergo surgery, according to a new analysis of Surveillance, Epidemiology and End Results-Medicare linked data.

Given advances in operative treatment of early-stage liver cancer, "there's probably a substantial number of people out there who could benefit from surgery who aren't getting the opportunity," Dr. Hari Nathan of Johns Hopkins University School of Medicine in Baltimore, the study's first author, told Reuters Health.

Surgery, Dr. Nathans and colleagues note this month in Annals of Surgery, represents patients' only chance for cure.

In patients with "fairly good liver function" and "fairly small tumors," Dr. Nathan said, "the survival rates have really improved over the past 15 to 20 years, and the options for them have really expanded."

The most common surgical treatments for HCC are ablation, resection, and transplant. All of these treatments have advanced in recent years, the researcher noted in an email. "The safety of doing liver resection has really improved," he said. "Our experience in operating on patients who have some element of liver disease has also improved...We've gotten smarter about how we choose the patients, we've gotten smarter about how we do the anesthesia."

To investigate how widely these therapies are being adopted for patients with early-stage disease, the researchers looked at 1,745 patients with tumors that were 5 cm or smaller, no metastases, no extrahepatic extension and no major vascular invasion.

Forty-seven percent received no surgical treatment, the researchers found. When they limited their analysis to patients with solitary tumors affecting only one lobe and in whom HCC had been microscopically confirmed, 33% had not been treated surgically. There were 535 patients who had no liver-related comorbidities, and 51% of these did not receive surgical treatment.

Multivariate analysis showed that older patients and those with lower incomes were less likely to receive surgical treatment. Alcoholic liver disease and portal hypertension also were associated with a lower likelihood of surgery, as were larger tumors and disease involving multiple lobes.

Patients treated at teaching hospitals, urban hospitals, American College of Surgeons Oncology Group hospitals, and National Cancer Institute Centers were more likely to receive surgical treatment.

The researchers also found low utilization of non-surgical treatments: 36% of patients in the study received neither surgical nor medical therapy. "We think there's likely a missed opportunity, that there are patients out there who could potentially benefit from some of these options, whether we're talking about the surgical options or the non-surgical options," Dr. Nathan said.

While some patients in the study may not have been candidates for surgical therapy for various reasons, the researcher added, this likely does not account for the full 47% of patients who weren't treated surgically.

"This is a field that's very much in flux," Dr. Nathan noted. "Some of the recent developments haven't percolated into every geographic region and every hospital. The capability and the familiarity are going to vary."

Also, he added, the fact that HCC has long been considered a very deadly disease could be a factor. "There's probably some element of fatalism about it, especially in an older patient, or in somebody who has other medical problems."

One drawback of the study, according to the researchers, is that it only included patients 66 and older, and studies have shown the median age of patients diagnosed with early HCC is 63. This means the findings apply to about half the adult population with HCC, Dr. Nathan said.

He and his colleagues conclude: "All patients with early HCC should be evaluated for surgical therapy to ensure that recent therapeutic advances for HCC are being applied in all appropriate cases. We suggest that increased referral of patients with HCC to centers with substantial liver surgery experience may ameliorate this problem."